Probably for Protective Purposes
by Gellie45
Summary: Tadashi Hamada is noticing major differences in his brother as Hiro enters puberty. Yet he can't decide if he likes the changes in his brother or not. (Hidashi, Hiro Hamada x Tadashi Hamada COMPLETED
1. Chapter 1

**His cheekbones were more sharp & handsome.**

**His chest, broader and muscular.**

**His** **body,**** more toned.**

**His height nearly exceeded Tadashi's own.**

**Hiro was growing up and Tadashi didn't like it.**

It's not that Tadashi minded Hiro's adolescent look. It was that Tadashi liked to appear like the stronger elder. Someone who looked like he could protect his loved ones, especially Hiro. Though he was not competitive about it, Hiro continued to grow as Tadashi didn't and he didn't like that.

"Wanna go to the café across the block with me?" Hiro asked, interrupting Tadashi's thoughts.

Aunt Cass began to groan. "Why on Earth would you want to go to a café RIGHT ACROSS THE STREET when you are currently standing in one that you get free meals from?! Also, I hear that their food is disgusting."

"I'm going because it's new and there is nothing else on my agenda for today." Hiro Responded with a cocky attitude. A cocky attitude that deserved ass whoopings, that of course Hiro never receives.

Aunt Cass just shrugged and returned to serving customers.

"So... ya wanna go?" Hiro asked again, directing towards his brother.

Tadashi took a minute, he knew what he was going to say already, but he wanted to stall time just to piss Hiro off. Or was it to see Hiro's begging face?

* * *

><p>"Why not." Tadashi smirked, after a moment of 'making up his mind'.<p>

As they walked, Tadashi couldn't keep his eyes off of his supposedly "younger" brother. Tadashi noticed some similarities to the baby brother that once stood before him. Like how Hiro still had a cocky grin on his face or that canyon of a gap between his teeth (which Aunt Cass told him to get fixed but he refused because he said it gave him 'character') Which it did, but more of a goofy one than what Hiro was thinking of, whatever he was thinking of. That also brought Tadashi new wonders. What did his brother think about? Robots? Inventions, ideas? Girl crushes, boy crushes? Tadashi also noted that Hiro was never really open about his sexuality with others. No one really minded that, except of course Tadashi.

* * *

><p>"Well, we're here Knuckles!"<p>

Hiro had always nicknamed Tadashi that because of his tendency to clench his fists as he walked. Tadashi never really knew why he did this, he just did. Maybe it was for protective purposes? Too bad that didn't matter now, Hiro was just as strong as he was.

Atop the Café stood a sign that read: "Leeb's Nuts". Hiro couldn't suppress his laughter. Tadashi grinned, more so towards his brother's squealing pig laughter but also at the sign.

"I guess 'nuts' isn't the best abbreviation for donuts huh?" Tadashi joked.

"The interior looks nice." The elder brother stated as they walked into the café.

"Yeah" Hiro agreed. Much nicer than Aunt Casses shop. This place makes hers look like a dump! I guess she has some competition." Hiro joked.

"Nah" Tadashi argued. "It's the food that really matters!"

"Then let's try some!" Hiro bounced, obviously enthusiastic.

They both ordered donuts. After one bite, they knew they were never returning to "Leeb's Nuts" again.

"Jesus fucking Christ!" Hiro spat. "Are you sure 'nuts' was an abbreviation for donuts? Or Leeb's ACTUAL NUTS?!"

Tadashi laughed, standing close to his brother as they walked home, his hands unconsciously clenched into fists. Probably for protective purposes.

"Back so soon? How was the café? Aunt Cass smirked as if she was already aware of how dreadful her nephews tastebuds felt after eating the other café's food.

"It was terrible." Tadashi admitted.

"Yep figured that." Aunt Cass proudly stated, with a hint of 'I told you so' in her voice.

After their little chats, the two brothers returned to their rooms. Their was a bit of an awkward silence between them, until Tadashi finally spoke.

"So, uh... What's new?" Tadashi said, sounding as if he was questioning his own question.

"Nothin' much, haven't had time to book myself in any botfights, hadn't had any time for friends. Only inventions." Hiro sighed.

"Hey, friends as just as important as inventing, maybe even more so. Human interaction is better than robotic." Tadashi appeared disappointed and a bit sad for his brother.

"Kinda funny to hear that coming out of someone who created a robotic nurse for me." Hiro smirked.

"Baymax isn't here to socialize with us Hiro, he's here to take care of us when others cannot." Tadashi was serious now, he didn't like people to try and prove him wrongly. He just guessed that it was just one of his many flaws.

"Ok, ok. Chill dude, I wasn't trying to bash on your latest creation, I was just messing with you."

Tadashi calmed himself and grinned, a grin that Hiro loved to see. One that could put someone out of misery and into happiness. At least that's how he felt when Tadashi smiled at him.

Suddenly Hiro's cheeks felt warm, he was blushing. The blush was very faint, as Tadashi didn't notice, Right? But Hiro began to feel awkward in his current position. Why was he blushing at his own brother? Especially if all he did was smile?

"Listen, I gotta work on upgrading... Uh something? Ok bye!" Hiro terribly lied, with a worried face.

"Ok?" Tadashi answered curiously.

As he left Tadashi's room and into the garage, he tried to shake off the feeling he was feeling but he just couldn't. His "Pubescent mood-swings" (As Baymax liked to call it) were acting up along with his hormones. Hiro thought about the situation he was in.

"Puberty isn't supposed to make someone...someone lust for their brother! So why the fuck is this happening to me?!" Hiro said in his mind.

While Hiro argued with his brain, Tadashi pondered as well. He thought about what had just occured.

"Hiro blushed at me." Tadashi said aloud.


	2. Chapter 2

Tadashi heard a loud thud coming from the room beneath him. What in the world is Hiro doing? Throwing bricks?! Tadashi was trying to keep concentrated on his studies, A new test was coming up on robotic anatomy and he didn't want to get a bad grade (even though he knew that wasn't going to happen).

"Hand me the screwdriver." Hiro commanded. Baymax obliged, handing him the tool. Hiro was upgrading Baymax, hoping to expand his Battery Life before needing to recharge. The task was difficult but what made it even more impossible was the fact that Hiro couldn't keep Tadashi's face out of his mind. Soon, he stopped working as he was dazed within his thoughts. He began to imagine what Tadashi would look like undressed. Probably all muscular and handsome.

"STOP!" A buzzing noise within Hiro's head told him that this was beyond wrong, but another part of him said to go along with it and see what'll happen. He began to hear foot steps nearing towards the work-room. He knew it was Tadashi. Quickly he pulled out the futon mattress in the room (Thinking of what could be if all goes according to plan) and pretended to be 'passed out' on his work desk. Still thinking about Tadashi and his body, making his skin warm in a full body blush. Blindsided to the fact that Baymax was still in the stance of when he was being 'operated' on.

Tadashi walked into the work room, only to see his younger, brother with his face implanted into his working desk.

"You ok?" Tadashi asked, concerned.

Hiro lifted his head and stared head on at Tadashi. Eyes half lidded and completely fogged with lust. Cheeks burning red as his hot skin could've been mistaken for a terrible fever. Tadashi looked shocked, he could've sworn he was dreaming, ...about his brother?

"H...Hiro?" Tadashi stuttered, but was suddenly interrupted by a huge, talking marshmallow

"Baymax? What, why are you activated?"

"Hiro was upgrading my Data Hard-Drive." Baymax plainly responded.

Before Tadashi asked anymore questions to Baymax, he glanced at Hiro. The closest thing Hiro resembled right now was a dog in heat. Hiro just stared at Tadashi, looking needy for him as if he was sick and his brother was the cure.

"Baymax, scan Hiro." Tadashi commanded.

With a quick glance, Baymax responded. "Scan complete. Hiro appears to have no physical injuries, but his hormonal level is very unstable. Common in male adolescence. Diagnosis; Puberty."

So to sum it up, Hiro was going through one of his teenage mood swings?! Or was he just horny? In Tadashi's mind he was blushing a deep red, but on the outside he appeared confused. (Tadashi knew how to keep his true emotions inside) So zoned out in thought, Tadashi nearly forgot that his hormonal brother was right infront of him. Literally. While Tadashi was deep in thought, Hiro had leaned closer towards his brother, unnoticed. Tadashi was about to speak up again, but was interrupted once more, this time by Hiro's lips.

Hiro was kissing his own brother, the brother that had raised him, and Hiro loved it. Tadashi couldn't believe how needy his brother really was or the fact that he was kissing his own brother! He tried gasping for air but Hiro did not permit it. Swirling his tounge inside Tadashi's mouth and locking lips with him did not lighten Hiro's craving for Tadashi's body. As they kissed, Hiro began to pull on Tadashi's shirt at an attept to take it off. At first Tadashi was hesitant, restraining Hiro's hand from traveling any further. To this, Hiro stopped kissing Tadashi, both gasping for air.

"Stop holding me back Tadashi. All these years I've only been able to fantasize about what this could be like. I need this." Hiro said, trembling with lust over his brother. Tadashi looked at his brother with wide eyes, seeing how much Hiro really did need this and how much Tadashi secretly wanted this to happen as well. He then let go of the grasp he had on his younger brother's arm, letting hands run free and remove his clothing to reveal a very muscular form. Hiro then planted small kisses all over Tadashi's stomach as a faint moan escaped Tadashi's lips. Hiro smirked, feeling accomplished from making his brother feel pleasure, then went back to working on his brothers body. Suddenly, Tadashi pushed Hiro up towards his face and lured him into a heated kiss. Tadashi now accepted what he was about to do, no going back. Hiro then broke the kiss and began to unbuckle Tadashi's belt. Once his jeans were removed, the only article of clothing holding Hiro away from Tadashi was the thin black fabric of boxers, covering the part of Tadashi that Hiro craved. Hiro then teased his brother by sucking at the fabric where a bulging manhood could be detected underneath. Hiro looked into Tadashi's eyes hungrily.

"You little bastard." Tadashi groaned, wanting more, so much more.

"Patience Tadashi." Hiro smirked. (While Secretly taking off Tadashi's boxers)

"You're one to talk!" Tadashi laughed, "You got me into this m- Ahh!" Suddenly Tadashi was gasping and moaning. Hiro was sucking on Tadashi's cock, taking it as far in his mouth as it would allow. Hiro was gagging on the organ with pleasure. Tadashi thought Hiro was hurting himself so he shot him a look of concern. Yet in reply, Hiro sucked even faster AND deeper on Tadashi's member and winked at him, giving Tadashi reassurance as well as driving him crazy. Hiro hummed with Tadashi's cock in his throat, the vibration tingling Tadashi as he moaned. Suddenly Tadashi cluched his hands into Hiro's hair, as he arched his back and gave one thrust into Hiro's mouth. Tadashi came within his brother's mouth and Hiro was happy to swallow. The taste was unfamiliar, but it wasn't a bad taste, especially when he remembered that it came from his brother... Literally. Tadashi and Hiro both panted, eager for more.

Tadashi randomly began to hoist himself up and flip Hiro over so that he was now on top. He preferred this position, it gave him a better view of his brother and of his surroundings. With this, he realized that they were on a futon couch that was already in the form of a bed. Had Hiro been expecting all this to happen from the start? Was Tadashi really that predictable? Going back into reality, he began to kiss Hiro. Taking in his lips and tounge in a sort of tug-of-war, while passionately taking off all articles of clothing on him. Tadashi began to touch Hiro's developing body, it was truly beautiful to see his younger brother like this, as well as finally being able to touch him in ways he only dreamed about. Hiro's stomach was surprisingly muscular and toned, this was odd to be so fit for a 15 (And a 1/2) year old. Not that Tadashi minded this, he found it quite sexy, actually. Slowly, Tadashi began to inch towards Hiro's private area. Planting kisses on his lower stomach. Now Tadashi was eye to 'eye' with Hiro's cock. What Tadashi saw shocked him, Hiro was huge! For his age, he shouldn't have been that large. Tadashi felt a tinge of jealousy, but dismissed it.

"Jeez Hiro!" Tadashi joked, "What in the world is Aunt Cass feeding you?!" Hiro smiled in response. Instead of using his mouth the whole time, Tadashi decided to use his hands on his brother. Pumping his member slowly in the beginning but faster as time progressed. Hiro let out loud moans and grunts of passion as Tadashi began to use his mouth as well as his hands. Tadashi had to admit, Hiro tasted damn good. As he continued to suck, Hiro's moans only became louder and filled with lust. While doing this, Tadashi glanced at Hiro, seeing his gaping mouth moan and his cheeks flushed. Finally, with one quick pump, Hiro yelled with pleasure as he came in Tadashi's hand (Luckly no one was nearby to hear it). Tadashi then took his cum-filled hand and licked it clean.

"Tastes like candy." Tadashi joked. Sounding very sexual in his voice, a voice that Hiro had never heard before but immediately adored.

"I want more!" Hiro whined. "I want to feel you inside me." That last sentence sounded almost like a whisper or a purr, either way, to hear those kind of words come from his little brothers mouth, drove Tadashi insane.

"Are you sure?" Tadashi asked, worried of potentially hurting his younger brother.

"Yes I'm sure! Now fuck my brains out." Hiro said, as if it was an order.

Tadashi applied a liberal amount of lubricant onto his cock, before rubbing himself against Hiro's opening. Both the brothers cheeks burned red at this. Hiro began to moan, which made Tadashi extremely hard. Slowly, he entered his brother. Hiro was so tight, it felt like the best feeling in the world for Tadashi, but for Hiro... not so much.

"Agh!" Hiro squeaked at the wince of pain he felt. Tadashi would've stopped but Hiro didn't give him any other sign to, so he didn't. Tadashi softly moaned as he went in and out of his sibling. As time went by, Tadashi began to move faster, hoping that Hiro didn't feel any pain (or could at least bear with it for a bit longer). At first, all Tadashi heard were grunts of displeasure and pain, but soon the sounds were of lust, moans and love.

"Ha-.. Harder." Hiro pleaded. Tadashi obliged, thrusting into his brother deeper and harder than before. Happy to hear that his brother was enjoying this as much as he was. To help cope, Tadashi began to touch Hiro's member. Rubbing it. Stroking it, until it became hard. By now, Tadashi was thrusting into his brother at full power. He was nearly positive that he was hitting Hiro's prostate. Hiro gasped and moaned, before yelling Tadashi's names as he came into his older brothers hand once more, and soon after Tadashi did too, with a great thrust, deep into his little brother. Cum oozed out of Hiro's tight hole.

"Aww, look at the mess you made!" Hiro giggled. Tadashi leaned forward and began to passionately kiss Hiro, tounge swirving inside. Tadashi then broke the kiss to plant more on Hiro's shoulder, and promptly sucking on one particular part of his neck. Hiro knew what Tadashi was trying to do. Yet Hiro allowed it, he was proud that he was now owned by someone, especially owned by Tadashi. Tadashi gave the hickey to Hiro out of love and to show that Hiro was his and his only.

From that day on, things were different between the two siblings, yet all still the same. The days were just as productive, but the nights weren't as quiet;)


End file.
